ReadableByteStreamController: byobRequest property

Value

A ReadableStreamBYOBRequest object instance, or null.

Examples

The example in Using readable byte streams > Creating a readable socket push byte stream shows how you use a byobRequest to transfer data (if it exists), or otherwise copy the data to the stream's internal queues using ReadableByteStreamController.enqueue().

The relevant code is reproduced below. If the byobRequest exists, data is read into controller.byobRequest.view, and then ReadableStreamBYOBRequest.respond() is called to signal the amount of data that is ready to transfer.

if (controller.byobRequest) {
  const v = controller.byobRequest.view;
  bytesRead = socket.readInto(v.buffer, v.byteOffset, v.byteLength);
  if (bytesRead === 0) {
    controller.close();
  }
  controller.byobRequest.respond(bytesRead);
} else {
  // Write to data using enqueue().
}

Specifications

Browser compatibility

See also

• Using readable byte streams
• ReadableByteStreamController